Method and system for pulse waveform variable edge control

Abstract

A method and system for providing variable edge control of pulse waveforms is provided. A positive edge DAC number is set so that the positive edge time of a first pulse waveform of some amplitude is substantially equal to some initial edge time. Similarly, a second positive edge DAC number associated with a second pulse waveform of different amplitude is set so that the positive edge time of the second pulse waveform also equals the initial edge time. Positive gain and offset factors are then generated so that a third positive edge DAC number associated with any pulse waveform may be calculated so that a desired positive edge time of that waveform is produced. Negative edge DAC numbers may be calculated in a similar manner so that the positive and negative edge times of a pulse waveform may be balanced, or more efficient methods may be used.

1. A method for providing variable edge control of pulse waveforms, comprising:
 selecting a first amplitude for a first pulse waveform; 
 setting a first positive edge digital-to-analog converter (DAC) number so that the positive edge time of the first pulse waveform is substantially equal to an initial edge time; 
 selecting a second amplitude for a second pulse waveform; 
 setting a second positive edge DAC number so that the positive edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 generating from the first and second positive edge DAC numbers a positive gain factor and a positive offset factor to be used in calculating a third positive edge DAC number so that the positive edge time of a third pulse waveform of a third amplitude substantially equals a desired edge time. 
 
   
   
     2. The method of  claim 1 , wherein the generating step comprises:
 multiplying the difference between the first and second positive edge DAC numbers by the initial edge time and a path gain, divided by 0.8 and the difference between the first and second amplitudes, to obtain the positive gain factor; and 
 subtracting from the first positive edge DAC number the difference between the first and second positive edge DAC numbers, multiplied by the first amplitude, divided by the difference between the first and second amplitudes, to obtain the positive offset factor, whereby the third positive edge DAC number is the positive gain factor, multiplied by 0.8 and the third amplitude, divided by the path gain and the desired edge time, plus the positive offset factor. 
 
   
   
     3. The method of  claim 1 , further comprising:
 setting a first negative edge DAC number so that the negative edge time of the first pulse waveform is substantially equal to the initial edge time; and 
 adding together the first positive and negative edge DAC numbers to obtain a DAC sum, whereby a third negative edge DAC number producing a negative edge time for the third pulse waveform equal to the desired edge time is the difference between the DAC sum and the third positive edge DAC number. 
 
   
   
     4. The method of  claim 1 , further comprising:
 setting a second negative edge DAC number so that the negative edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 adding together the second positive and negative edge DAC numbers to obtain a DAC sum, whereby a third negative edge DAC number producing a negative edge time for the third pulse waveform equal to the desired edge time is the difference between the DAC sum and the third positive edge DAC number. 
 
   
   
     5. The method of  claim 1 , further comprising:
 setting a first negative edge DAC number so that the negative edge time of the first pulse waveform is substantially equal to the initial edge time; 
 setting a second negative edge DAC number so that the negative edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 adding together the first and second positive DAC numbers and the first and second negative edge DAC numbers, divided by two, to obtain a DAC sum, whereby a third negative edge DAC number producing a negative edge time for the third pulse waveform equal to the desired edge time is the difference between the DAC sum and the third positive edge DAC number. 
 
   
   
     6. The method of  claim 1 , further comprising:
 setting a first negative edge DAC number so that the negative edge time of the first pulse waveform is substantially equal to the initial edge time; 
 setting a second negative edge DAC number so that the negative edge time of the second pulse waveform is substantially equal to the initial edge time; 
 multiplying the difference between the first and second negative edge DAC numbers by the initial edge time and a path gain, divided by 0.8 and the difference between the first and second amplitudes, to obtain a negative gain factor; and 
 subtracting from the first negative edge DAC number the difference between the first and second negative edge DAC numbers, multiplied by the first amplitude, divided by the difference between the first and second amplitudes, to obtain a negative offset factor, whereby a third negative edge DAC number producing a negative edge time for the third pulse waveform equal to the desired edge time is the negative gain factor, multiplied by 0.8 and the third amplitude, divided by the path gain and the desired edge time, plus the negative offset factor. 
 
   
   
     7. A program storage medium readable by a computer system embodying a program executable by the computer system to perform the method of  claim 1 . 
   
   
     8. A method for providing variable edge control of pulse waveforms, comprising:
 selecting a first amplitude for a first pulse waveform; 
 setting a first negative edge digital-to-analog converter (DAC) number so that the negative edge time of the first pulse waveform is substantially equal to an initial edge time; 
 selecting a second amplitude for a second pulse waveform; 
 setting a second negative edge DAC number so that the negative edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 generating from the first and second negative edge DAC numbers a negative gain factor and a negative offset factor to be used in calculating a third negative edge DAC number so that the negative edge time of a third pulse waveform of a third amplitude substantially equals a desired edge time. 
 
   
   
     9. The method of  claim 8 , wherein the generating step comprises:
 multiplying the difference between the first and second negative edge DAC numbers by the initial edge time and a path gain, divided by 0.8 and the difference between the first and second amplitudes, to obtain the negative gain factor; and 
 subtracting from the first negative edge DAC number the difference between the first and second negative edge DAC numbers, multiplied by the first amplitude, divided by the difference between the first and second amplitudes, to obtain the negative offset factor, whereby the third negative edge DAC number is the negative gain factor, multiplied by 0.8 and the third amplitude, divided by the path gain and the desired edge time, plus the negative offset factor. 
 
   
   
     10. The method of  claim 8 , further comprising:
 setting a first positive edge DAC number so that the positive edge time of the first pulse waveform is substantially equal to the initial edge time; and 
 adding together the first positive and negative edge DAC numbers to obtain a DAC sum, whereby a third positive edge DAC number producing a positive edge time for the third pulse waveform equal to the desired edge time is the difference between the DAC sum and the third negative edge DAC number. 
 
   
   
     11. The method of  claim 8 , further comprising:
 setting a second positive edge DAC number so that the positive edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 adding together the second positive and negative edge DAC numbers to obtain a DAC sum, whereby a third positive edge DAC number producing a positive edge time for the third pulse waveform equal to the desired edge time is the difference between the DAC sum and the third negative edge DAC number. 
 
   
   
     12. The method of  claim 8 , further comprising:
 setting a first positive edge DAC number so that the positive edge time of the first pulse waveform is substantially equal to the initial edge time; 
 setting a second positive edge DAC number so that the positive edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 adding together the first and second positive DAC numbers and the first and second negative edge DAC numbers, divided by two, to obtain a DAC sum, whereby a third positive edge DAC number producing a positive edge time for the third pulse waveform equal to the desired edge time is the difference between the DAC sum and the third negative edge DAC number. 
 
   
   
     13. The method of  claim 8 , further comprising:
 setting a first positive edge DAC number so that the positive edge time of the first pulse waveform is substantially equal to the initial edge time; 
 setting a second positive edge DAC number so that the positive edge time of the second pulse waveform is substantially equal to the initial edge time; 
 multiplying the difference between the first and second positive edge DAC numbers by the initial edge time and a path gain, divided by 0.8 and the difference between the first and second amplitudes, to obtain a positive gain factor; and 
 subtracting from the first positive edge DAC number the difference between the first and second positive edge DAC numbers, multiplied by the first amplitude, divided by the difference between the first and second amplitudes, to obtain a positive offset factor, whereby a positive edge DAC number producing a positive edge time for the third pulse waveform equal to the desired edge time is the positive gain factor, multiplied by 0.8 and the third amplitude, divided by the path gain and the desired edge time, plus the positive offset factor. 
 
   
   
     14. A program storage medium readable by a computer system embodying a program executable by the computer system to perform the method of  claim 8 . 
   
   
     15. A system for providing variable edge control of pulse waveforms, comprising:
 means for selecting a first amplitude for a first pulse waveform; 
 means for setting a first positive edge digital-to-analog converter (DAC) number so that the positive edge time of the first pulse waveform is substantially equal to an initial edge time; 
 means for selecting a second amplitude for a second pulse waveform; 
 means for setting a second positive edge DAC number so that the positive edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 means for generating from the first and second positive edge DAC numbers a positive gain factor and a positive offset factor to be used in calculating a third positive edge DAC number so that the positive edge time of a third pulse waveform of a third amplitude substantially equals a desired edge time. 
 
   
   
     16. A system for providing variable edge control of pulse waveforms, comprising:
 means for selecting a first amplitude for a first pulse waveform; 
 means for setting a first negative edge digital-to-analog converter (DAC) number so that the negative edge time of the first pulse waveform is substantially equal to an initial edge time; 
 means for selecting a second amplitude for a second pulse waveform; 
 means for setting a second negative edge DAC number so that the negative edge time of the second pulse waveform is substantially equal to the initial edge time; and 
 means for generating from the first and second negative edge DAC numbers a negative gain factor and a negative offset factor to be used in calculating a third negative edge DAC number so that the negative edge time of a third pulse waveform of a third amplitude substantially equals a desired edge time.